Milling-cutter.



No.. 889,829. PATENTED JUNE 2, 1908.

A. L. VALENTINE L C. G. DAHL.

A MILLING GUTTER.

APPLIGATIQN FILED APR.1B,1906.

unirse sirarns 'Param' casio-n 'AUGUST L. VALENTINE AND CARL G. DAHL, 'OF HARTFORD, CONNECTICUT, ASSIGNORS TO PRATT &` WHITNEY COMPANY, OF HARTFORD. CONNECTICUT, A CORPORATION OF NEW MILLING-CUTTER.

v Specification of Letters Patent.

Patented June 2, 1908.

Application filed April 18, 1906. Serial No. 312,405.

proved construction of the teeth of the same,

whereby division of the cutting-action of said teeth is provided for, clogging due toilowage of the metal or of the chips i sprevented, and a cut having clean, sharp surfaces is the result.

Afurther object of the invention is the pro-v vision of a tool of the character mentioned provided with teeth having grooved or re- ;cessed edge-surfaces, and cutting-edges at is a side elevation of a` milling-cutter ernbodying the invention. Fig. 2 is an edge view of said cutter; and Figs. 3, 4, and 5 are detail sectional views, illustrating the action of the alternate teeth upon'rnaterial undergoi'nfr operation.

LiIie numerals designate similar parts throughout the severalviews.

Referring to the drawings, the numeral 5 designates a cutter of the kind described, said cutter having an axial opening 6, in 4its hub for the reception of its supporting shaft or arbor. On its periphery this cutter is provided with a series of teeth 7, eachtooth having a groove or depression 8, shown located at 'the center of its cutting-edge, although it may be differently disposed., and also having straight cutting-edges 9, one at each side of said groove or depression. Following each tooth 7 is a tooth 1'0 having a straight cutting-edge 11, and side cutting edges 12 dverging from said 4intermediate straight edge 11.

that theteeth 7 and 10 are alternately arcision is the result.

out unnecessary t will be understood from the drawings ranged with relationto each other around the periphery ofthe cutter-disk, and that` the cutting-edges 9 of each tooth 7 and 1 1 of each tooth 10 are concentric to the axis of the tool.-

lo provide clearance. for the chips, each alternate tooth 7 is inclined on its sides as at 7 and each alternate tooth 10 isl similarly inclined as at 10. From what has been stated it follows that the action of the cutting-edges 9 of the teeth 7 is to reduce'materialnn lines 13 and leave intermediate said lines a slight protuberance or rib 14, conforming in shape to that of the recess 8 (see Fig. 3).

Attention now being invited to Fig. 4, it will be seen that the cutting-edge 11 of each alternate tooth 10, will remove the slight rib or rotuberance 14, and will leave the work wit slightly inclined walls 15 at its sides, as shown in said figure, said inclined walls being removed by the following straight-cuttingedges 9 of the next alternate tooth 7, so that the result is -either a groove having a straight bottom wall 16, Fig. 5, or work of any klnd underoperation having a right-line surface when the'feed is arrested. In this manner a division of labor is carried out by alternating the teeth of the improved cutter, and the 'chips produced by the cuttin -action yfind clearance, so that clogg' g is e ectually prevented.

While useful on metal of any material, the

cutter may be employed with advantage with what are known as the soft metals," such as aluminum, cfpper and others having similar qualities. hen. such soft metals vare subjected to a milling-operation, cleancutting of the chi s, as in the case of iron and steel, is frequent y impossible on account -of the tendency of said material, as the tooth starts to vremove the chip therefrom, tobecome dis laced and flow laterally, thereby causing c ogging, while in a cutter of the kind mentioned this tendency ofthe material is entirely obviated, anda clean and sharp in- It is found in practice that a tool having alternate teeth of the character above set forth will work rapidly and accurately with- ,17.* A tool of the class described, c omp1'isin iction` upon the material ico a disk having sets of peripheral teeth, each or depression, and the following tooth having tooth of one set being rooved and provided one euttingdge at its end, and' other outwith outting-edges on t` e sides of the groove, ting-edges diverging from said end cutting#v 15 l and each tooth of the other set having a main edg cutting-edge opposite the groove of the re- In testimony whereof we. ax our signah oeding tooth, and also having cutting-e ges tures in presence of two Witnesses, vat Hartdiverging lfrom said main cutting-edge., ford, Conni, this 26th day of March, 1906. 2i A milling-cutter comprising a disk hav- AUGUST L. VALENTINE. ing teeth cono'ntrie with its axis, and alter- C. G. DAHL.

mately g dis osed substantially as described, Witnesses: one tooth Iheilig Erovidd with two outting- F. G. EoHoE,

edges separate y an intermediate groove E. D. CLARK.' 

